Abstract: A method includes etching a semiconductor substrate to form a trench between a first semiconductor strip and a second semiconductor strip. The first semiconductor strip has a first width at about 5 nm below a top of the first semiconductor strip and a second width at about 60 nm below the top of the first semiconductor strip. The first width is smaller than about 5 nm, and the second width is smaller than about 14.5 nm. The trench is filled with dielectric materials to form an isolation region, which is recessed to have a depth. A top portion of the first semiconductor strip protrudes higher than the isolation region to form a protruding fin. The protruding fin has a height smaller than the depth. A gate stack is formed to extend on a sidewall and a top surface of the protruding fin.

Abstract: An embodiment is a semiconductor structure. The semiconductor structure includes a substrate. A fin is on the substrate. The fin includes silicon germanium. An interfacial layer is over the fin. The interfacial layer has a thickness in a range from greater than 0 nm to about 4 nm. A source/drain region is over the interfacial layer. The source/drain region includes silicon germanium.

Abstract: A method includes etching a trench in a substrate adjacent to a gate structure, wherein the trench includes a bottom surface and a tip portion extending under a spacer of the gate structure. The method further includes epitaxially growing a first semiconductor material in the trench, wherein the first semiconductor material covers an entirety of the bottom surface of the trench, and the first semiconductor material grows in the tip portion. The method further includes epitaxially growing a second semiconductor material in the trench, wherein the second semiconductor material is different from the first semiconductor material, the second semiconductor material covers the first semiconductor material, and the second semiconductor material directly contacts the substrate between the bottom surface of the trench and the tip portion.

Abstract: An embodiment is a semiconductor structure. The semiconductor structure includes a substrate. A fin is on the substrate. The fin includes silicon germanium. An interfacial layer is over the fin. The interfacial layer has a thickness in a range from greater than 0 nm to about 4 nm. A source/drain region is over the interfacial layer. The source/drain region includes silicon germanium.

Abstract: A semiconductor device includes a first device region and a second device region. The first device region includes a first source/drain region extending from a substrate and a first and a second pair of spacers. The first source/drain region extends between the first pair of spacers and the second pair of spacers. The first pair of spacers and the second pair of spacers have a first height. The second device region includes a second and a third source/drain region extending from the substrate and a third and a fourth pair of spacers. The third source/drain region is separate from the second source/drain region. The second source/drain region extends between the third pair of spacers. The third source/drain region extends between the fourth pair of spacers. The third pair of spacers and the fourth pair of spacers have a second height greater than the first height.

Abstract: A method includes forming a fin over a substrate, forming an isolation region adjacent the fin, forming a dummy gate structure over the fin, and recessing the fin adjacent the dummy gate structure to form a first recess using a first etching process. The method also includes performing a plasma clean process on the first recess, the plasma clean process including placing the substrate on a holder disposed in a process chamber, heating the holder to a process temperature between 300° C. and 1000° C., introducing hydrogen gas into a plasma generation chamber connected to the process chamber, igniting a plasma within the plasma generation chamber to form hydrogen radicals, and exposing surfaces of the recess to the hydrogen radicals. The method also includes epitaxially growing a source/drain region in the first recess.

Abstract: A method includes forming a gate structure over fins protruding from a semiconductor substrate; forming an isolation region surrounding the fins; depositing a spacer layer over the gate structure and over the fins, wherein the spacer layer fills the regions extending between pairs of adjacent fins; performing a first etch on the spacer layer, wherein after performing the first etch, first remaining portions of the spacer layer that are within inner regions extending between pairs of adjacent fins have a first thickness and second remaining portions of the spacer layer that are not within the inner regions have a second thickness less than the first thickness; and forming an epitaxial source/drain region adjacent the gate structure and extending over the fins, wherein portions of the epitaxial source/drain region within the inner regions are separated from the first remaining portions of the spacer layer.

Abstract: An integrated circuit structure includes a gate stack over a semiconductor substrate, and a silicon germanium region extending into the semiconductor substrate and adjacent to the gate stack. The silicon germanium region has a top surface, with a center portion of the top surface recessed from edge portions of the top surface to form a recess. The edge portions are on opposite sides of the center portion.

Abstract: A device includes a substrate and a gate structure over the substrate. The device further includes source/drain (S/D) features in the substrate. At least one of the S/D features is located in a trench. The at least one S/D feature includes a first semiconductor material covering an entirety of a bottom surface of the trench. The at least one S/D feature further includes a second semiconductor material over the first semiconductor material. The at least one S/D feature further includes a third semiconductor material over the second semiconductor material. The second semiconductor material has a composition different from the first semiconductor material and the third semiconductor material. The first semiconductor material includes physically discontinuous portions directly contacting the substrate. The second semiconductor material surrounds the third semiconductor material.

Abstract: An integrated circuit structure includes a gate stack over a semiconductor substrate, and an opening extending into the semiconductor substrate, wherein the opening is adjacent to the gate stack. A first silicon germanium region is disposed in the opening, wherein the first silicon germanium region has a first germanium percentage. A second silicon germanium region is over the first silicon germanium region. The second silicon germanium region comprises a portion in the opening. The second silicon germanium region has a second germanium percentage greater than the first germanium percentage. A silicon cap substantially free from germanium is over the second silicon germanium region.

Abstract: A method includes forming a semiconductor fin protruding higher than top surfaces of isolation regions. A top portion of the semiconductor fin is formed of a first semiconductor material. A semiconductor cap layer is formed on a top surface and sidewalls of the semiconductor fin. The semiconductor cap layer is formed of a second semiconductor material different from the first semiconductor material. The method further includes forming a gate stack on the semiconductor cap layer, forming a gate spacer on a sidewall of the gate stack, etching a portion of the semiconductor fin on a side of the gate stack to form a first recess extending into the semiconductor fin, recessing the semiconductor cap layer to form a second recess directly underlying a portion of the gate spacer, and performing an epitaxy to grow an epitaxy region extending into both the first recess and the second recess.

Abstract: A method for forming a semiconductor structure includes forming a gate structure over a substrate. The method also includes forming a spacer on a sidewall of the gate structure. The method also includes forming a source/drain recess beside the spacer. The method also includes treating the source/drain recess and partially removing the spacers in a first cleaning process. The method also includes treating the source/drain recess with a plasma process after performing the first cleaning process. The method also includes treating the source/drain recess in a second cleaning process after treating the source/drain recess with the plasma process. The method also includes forming a source/drain structure in the source/drain recess after performing the second cleaning process.

Abstract: A method includes forming a fin over a substrate, forming an isolation region adjacent the fin, forming a dummy gate structure over the fin, and recessing the fin adjacent the dummy gate structure to form a first recess using a first etching process. The method also includes performing a plasma clean process on the first recess, the plasma clean process including placing the substrate on a holder disposed in a process chamber, heating the holder to a process temperature between 300° C. and 1000° C., introducing hydrogen gas into a plasma generation chamber connected to the process chamber, igniting a plasma within the plasma generation chamber to form hydrogen radicals, and exposing surfaces of the recess to the hydrogen radicals. The method also includes epitaxially growing a source/drain region in the first recess.

Abstract: A method includes forming a gate structure over fins protruding from a semiconductor substrate; forming an isolation region surrounding the fins; depositing a spacer layer over the gate structure and over the fins, wherein the spacer layer fills the regions extending between pairs of adjacent fins; performing a first etch on the spacer layer, wherein after performing the first etch, first remaining portions of the spacer layer that are within inner regions extending between pairs of adjacent fins have a first thickness and second remaining portions of the spacer layer that are not within the inner regions have a second thickness less than the first thickness; and forming an epitaxial source/drain region adjacent the gate structure and extending over the fins, wherein portions of the epitaxial source/drain region within the inner regions are separated from the first remaining portions of the spacer layer.

Abstract: A method of forming a semiconductor device includes depositing a film over a dielectric layer. The dielectric layer is over a first fin, a second fin, and within a trench between the first fin and the second fin. The method further includes etching top portions of the film, performing a treatment on the dielectric layer to remove impurities after etching the top portions of the film, and filling the trench over the remaining portions of the film. The treatment includes bombarding the dielectric layer with radicals.

Abstract: Embodiments provide a way of treating source/drain recesses with a high heat treatment and an optional hydrogen plasma treatment. The high heat treatment smooths the surfaces inside the recesses and remove oxides and etching byproducts. The hydrogen plasma treatment enlarges the recesses vertically and horizontally and inhibits further oxidation of the surfaces in the recesses.

Abstract: A method includes forming a semiconductor fin protruding higher than top surfaces of isolation regions. A top portion of the semiconductor fin is formed of a first semiconductor material. A semiconductor cap layer is formed on a top surface and sidewalls of the semiconductor fin. The semiconductor cap layer is formed of a second semiconductor material different from the first semiconductor material. The method further includes forming a gate stack on the semiconductor cap layer, forming a gate spacer on a sidewall of the gate stack, etching a portion of the semiconductor fin on a side of the gate stack to form a first recess extending into the semiconductor fin, recessing the semiconductor cap layer to form a second recess directly underlying a portion of the gate spacer, and performing an epitaxy to grow an epitaxy region extending into both the first recess and the second recess.

Abstract: A method for forming a fin field effect transistor device structure includes forming a fin structure over a substrate. The method also includes forming a gate structure across the fin structure. The method also includes forming a source/drain recess adjacent to the gate structure. The method also includes wet cleaning the source/drain recess in a first wet cleaning process. The method also includes treating the source/drain recess with a plasma process. The method also includes wet cleaning the source/drain recess in a second wet cleaning process after treating the source/drain recess via the plasma process. The method also includes growing a source/drain epitaxial structure in the source/drain recess.

Abstract: A semiconductor device having an improved source/drain region profile and a method for forming the same are disclosed. In an embodiment, a method includes etching one or more semiconductor fins to form one or more recesses; and forming a source/drain region in the one ore more recesses, the forming the source/drain region including epitaxially growing a first semiconductor material in the one or more recesses at a temperature of 600° C. to 800° C., the first semiconductor material including doped silicon germanium; and conformally depositing a second semiconductor material over the first semiconductor material at a temperature of 300° C. to 600° C., the second semiconductor material including doped silicon germanium and having a different composition than the first semiconductor material.

Abstract: A fin structure on a substrate is disclosed. The fin structure can comprises a first epitaxial region and a second epitaxial region separated by a dielectric region, a merged epitaxial region on the first epitaxial region and the second epitaxial region, an epitaxial buffer region on a top surface of the merged epitaxial region, and an epitaxial capping region on the buffer epitaxial region and side surfaces of the merged epitaxial region.